1,570 research outputs found
Differential proteomes of the cyanobacterium Cyanothece sp. CCY 0110 upon exposure to heavy metals
The proteomes of the highly efficient extracellular polymeric substances (EPS)-producer cyanobacterium Cyanothece sp. CCY 0110, grown in medium supplemented with an essential metal (Cu(2+)) or a non-essential metal (Cd(2+)),were compared using iTRAQ technology. The data were obtained within a larger study that evaluated the overall effects of different heavy metals on growth/survival, EPS production and ultrastructure of this cyanobacterium [1]. To allow a broader understanding of the strategies triggered to coupe with toxic effects of the metals, Cyanothece's proteomes were evaluated after chronic and acute exposure to Cu(2+) and Cd(2+) in two independent 8-plex iTRAQ studies. For the chronic exposure 0.1 mg/l of Cu(2+) or 5 mg/l of Cd(2+) were used for 10 and 20 days, while in the acute experiments the cells were exposed to 10× these concentrations for 24 h. 202 and 268 proteins were identified and quantified for studies 1 (Cu(2+)) and 2 (Cd(2+)), respectively. The majority of the proteins with significant fold changes were associated with photosynthesis, CO2 fixation and carbohydrate metabolism, translation, and nitrogen and amino acid metabolism
Influência do número de gemas, presença ou ausência de folhas e posição do explante na multiplicação in vitro da batata
Sistema de plantio de milho em fileiras duplas e simples em consórcio com o feijoeiro comum
Tensor Correlations Measured in 3He(e,e'pp)n
We have measured the 3He(e,e'pp)n reaction at an incident energy of 4.7 GeV
over a wide kinematic range. We identified spectator correlated pp and pn
nucleon pairs using kinematic cuts and measured their relative and total
momentum distributions. This is the first measurement of the ratio of pp to pn
pairs as a function of pair total momentum, . For pair relative
momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low and
rises to approximately 0.5 at large . This shows the dominance of
tensor over central correlations at this relative momentum.Comment: 4 pages, 4 figures, submitted to PR
Differential cross section and recoil polarization measurements for the gamma p to K+ Lambda reaction using CLAS at Jefferson Lab
We present measurements of the differential cross section and Lambda recoil
polarization for the gamma p to K+ Lambda reaction made using the CLAS detector
at Jefferson Lab. These measurements cover the center-of-mass energy range from
1.62 to 2.84 GeV and a wide range of center-of-mass K+ production angles.
Independent analyses were performed using the K+ p pi- and K+ p (missing pi -)
final-state topologies; results from these analyses were found to exhibit good
agreement. These differential cross section measurements show excellent
agreement with previous CLAS and LEPS results and offer increased precision and
a 300 MeV increase in energy coverage. The recoil polarization data agree well
with previous results and offer a large increase in precision and a 500 MeV
extension in energy range. The increased center-of-mass energy range that these
data represent will allow for independent study of non-resonant K+ Lambda
photoproduction mechanisms at all production angles.Comment: 22 pages, 16 figure
Measurement of the Nucleon Structure Function F2 in the Nuclear Medium and Evaluation of its Moments
We report on the measurement of inclusive electron scattering off a carbon
target performed with CLAS at Jefferson Laboratory. A combination of three
different beam energies 1.161, 2.261 and 4.461 GeV allowed us to reach an
invariant mass of the final-state hadronic system W~2.4 GeV with four-momentum
transfers Q2 ranging from 0.2 to 5 GeV2. These data, together with previous
measurements of the inclusive electron scattering off proton and deuteron,
which cover a similar continuous two-dimensional region of Q2 and Bjorken
variable x, permit the study of nuclear modifications of the nucleon structure.
By using these, as well as other world data, we evaluated the F2 structure
function and its moments. Using an OPE-based twist expansion, we studied the
Q2-evolution of the moments, obtaining a separation of the leading-twist and
the total higher-twist terms. The carbon-to-deuteron ratio of the leading-twist
contributions to the F2 moments exhibits the well known EMC effect, compatible
with that discovered previously in x-space. The total higher-twist term in the
carbon nucleus appears, although with large systematic uncertainites, to be
smaller with respect to the deuteron case for n<7, suggesting partial parton
deconfinement in nuclear matter. We speculate that the spatial extension of the
nucleon is changed when it is immersed in the nuclear medium.Comment: 37 pages, 15 figure
Avaliação sistêmica do setor industrial brasileiro: 1995-2009
Resumo O presente artigo busca avaliar o setor industrial sob uma ótica distinta da que tem sido utilizada quando se trata de industrialização/desindustrialização. O objetivo é analisar o caráter sistêmico do setor industrial a partir do método de insumo-produto, por meio de indicadores de intensidade direta e intensidade direta mais indireta da indústria. Por esta medida, é possível deixar mais clara a contribuição do artigo, ou seja, fornecer uma medida de integração produtiva do setor industrial com os demais setores, de modo a verificar se a indústria tem ganhado importância relativa como setor articulador das atividades produtivas
Measurement of the nuclear multiplicity ratio for hadronization at CLAS
The influence of cold nuclear matter on lepto-production of hadrons in
semi-inclusive deep inelastic scattering is measured using the CLAS detector in
Hall B at Jefferson Lab and a 5.014 GeV electron beam. We report the
multiplicity ratios for targets of C, Fe, and Pb relative to deuterium as a
function of the fractional virtual photon energy transferred to the
and the transverse momentum squared of the . We find that the
multiplicity ratios for are reduced in the nuclear medium at high
and low , with a trend for the transverse momentum to be
broadened in the nucleus for large .Comment: Submitted to Phys. Lett.
A Bayesian analysis of pentaquark signals from CLAS data
We examine the results of two measurements by the CLAS collaboration, one of
which claimed evidence for a pentaquark, whilst the other found no
such evidence. The unique feature of these two experiments was that they were
performed with the same experimental setup. Using a Bayesian analysis we find
that the results of the two experiments are in fact compatible with each other,
but that the first measurement did not contain sufficient information to
determine unambiguously the existence of a . Further, we suggest a
means by which the existence of a new candidate particle can be tested in a
rigorous manner.Comment: 5 pages, 3 figure
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